import { describe, expect, it } from "vitest";
import {
	activeAttachments,
	applyCompletion,
	detectTrigger,
	fileItem,
	matchesQuery,
	skillItems,
} from "./mentions";

describe("detectTrigger", () => {
	it("opens the file selector on @ at the start or after a space", () => {
		expect(detectTrigger("@", 1)).toEqual({
			kind: "file",
			query: "",
			start: 0,
		});
		expect(detectTrigger("look at @src/ma", 15)).toEqual({
			kind: "file",
			query: "src/ma",
			start: 8,
		});
	});

	it("ignores @ glued to a word or followed by whitespace", () => {
		expect(detectTrigger("mail me@example", 15)).toBeNull();
		expect(detectTrigger("@src done", 9)).toBeNull();
	});

	it("only looks before the caret", () => {
		expect(detectTrigger("@a @b", 2)).toEqual({
			kind: "file",
			query: "a",
			start: 0,
		});
	});

	it("opens the skill selector on a leading slash only", () => {
		expect(detectTrigger("/", 1)).toEqual({
			kind: "skill",
			query: "",
			start: 0,
		});
		expect(detectTrigger("/qua", 4)).toEqual({
			kind: "skill",
			query: "qua",
			start: 0,
		});
		expect(detectTrigger("/quality now", 12)).toBeNull();
		expect(detectTrigger("see /path", 9)).toBeNull();
	});
});

describe("applyCompletion", () => {
	it("replaces the trigger and query, adds a space and moves the caret", () => {
		const trigger = detectTrigger("look at @src/ma please", 15);
		if (!trigger) {
			throw new Error("expected a trigger");
		}
		expect(
			applyCompletion("look at @src/ma please", trigger, "@src/main.go"),
		).toEqual({
			text: "look at @src/main.go  please",
			caret: "look at @src/main.go ".length,
		});
	});

	it("handles the slash trigger at the start", () => {
		expect(
			applyCompletion(
				"/qu",
				{ kind: "skill", query: "qu", start: 0 },
				"/quality",
			),
		).toEqual({
			text: "/quality ",
			caret: 9,
		});
	});
});

describe("skillItems", () => {
	it("merges skills and commands, skills winning, sorted by name", () => {
		const items = skillItems(
			[
				{
					name: "quality",
					description: "Measure quality",
					path: "/p",
					source: "project",
				},
				{
					name: "review",
					description: "Skill review",
					path: "/p2",
					source: "user",
				},
			],
			[
				{ name: "review", description: "Command review" },
				{ name: "compact", description: "Summarise" },
			],
		);
		expect(items.map((i) => [i.label, i.source, i.insert])).toEqual([
			["compact", "command", "/compact"],
			["quality", "skill", "/quality"],
			["review", "skill", "/review"],
		]);
	});

	it("filters on label or description, case-insensitively", () => {
		const [item] = skillItems(
			[],
			[{ name: "compact", description: "Summarise the thread" }],
		);
		expect(matchesQuery(item, "COMP")).toBe(true);
		expect(matchesQuery(item, "thread")).toBe(true);
		expect(matchesQuery(item, "zzz")).toBe(false);
		expect(matchesQuery(item, "")).toBe(true);
	});
});

describe("fileItem / activeAttachments", () => {
	it("builds an @ insertion carrying the attachment", () => {
		expect(
			fileItem({ path: "/w/src/main.go", relPath: "src/main.go" }),
		).toMatchObject({
			insert: "@src/main.go",
			attachment: { path: "/w/src/main.go", name: "src/main.go" },
		});
	});

	it("drops attachments no longer mentioned and duplicates", () => {
		const attachments = [
			{ path: "/w/a.go", name: "a.go" },
			{ path: "/w/b.go", name: "b.go" },
			{ path: "/w/a.go", name: "a.go" },
		];
		expect(activeAttachments("see @a.go", attachments)).toEqual([
			{ path: "/w/a.go", name: "a.go" },
		]);
	});
});